How to Troubleshoot High IO Delay

[Jeffrey Roberts]

I have very high io delay, and I am not sure how to troubleshoot what is going on here, there is no load on the box and nothing should be creating a io delay at all, everything should be idle...

How can I troubleshoot to find out which VM or Service is causing the High IO Delay?

 

[LnxBil]

How can I troubleshoot to find out which VM or Service is causing the High IO Delay?

First, I/O delay is caused by the storage hardware, so you have to monitor the hardware via iostat. If you inspected this and hopefully find a culprit already, you can get to work on that.
If you want to find linux processes that cause I/O in general, you can look at iotop and identify e.g. QEMU and then you find in its arguments the ID of your VM.

 

[Jeffrey Roberts]

Perfect, that was exactly what I was looking for, thank you